/Engine/Source/Editor/UnrealEd/Public/IPIEAuthorizer.h
Used to gate play-in-editor functionality, where a PIE session may be undesirable given some external plugin's state.
False to block play-in-editor from continuing, true to allow.
bool RequestPIEPermission ( bool bIsSimulateInEditor, [FString](API\Runtime\Core\Containers\FString) & OutReason ) const